Bearing for drill stems



4 Sheets-Sheet 1 J- GRANT Filed Aug. 15, 1927 BEARING FOR DRILL STEMS Jan. 13, 1931.

[7212211 to! JOHN GRANT .fifl-orney Jan. 13, 1931. 4 GRANT BEARING FOR DRILL STEMS Filed Aug. 15, 1927 4 Sheets-Sheet 4 fiver? for I JOH GRANT I Q 1 Y STATES F TE- e, 5 i

I their easy mounting and dis-mounting, 'it' Figure 8'is a section on line 88 of Fig.

Patented Jamie, 1931 it r e j I 5 .Jonnerumnor LosANGELiisQoALmonmA' v A "BEARING Forename-swims i i r Application filed August 1 5, 1927,; 'Seria1N'o'. 21 2 ,907.

This invention has to do generally with 5 tion, r'elative1y cheapand easy to manuface .thedeep w'ell drilli-ngart, and is more parture,*assemble and install, and. which has ticularly concerned with devices forprotect; such characteristics that it efl'ectively re; ing well casings from. the'abrasive effects, sistskthe tremendous.strainsto which it is etc, of drillstem s rotating therein; f exposed. -VVl1ile my invention has other 'obp It has been proposed and attempted to jects and presentsother novel features, these. reduce to a minimum or eliminate these most may be discussed to better advantage as-thef undesirable effects on casings by the profollowing detailed"description .progresses. vision of antifriction'bearings at intervals, Re'ferenoe'will behadto the accompanying along the stem','the stem thus being'ltept out drawinggyin Whichi l p i I ofdireet Contact with theoasmg. Atyplcal Figure lais a fragmentary sectional view bearing includesrelatively rotatable inner through a deep Well casing'showing in eleand outer sleeves, the'inner sleeve being convat-ion therein an" embodiment of my 'in- I neete'dto the drill stem for rotation therevention "applied to. the drill stem. I 1 with andthe outer sleevebeing of greater Figure l is an enlargedfragmentary sec- 5 diameter than the tool joints an'd' being tion on" line-1 1 of Fig. 1a, parts of the p adapted to engage thecasing peripherally bearing'a'nd tool joint being shown in eleva ..when the stem swings off centerpthe outertion. j f

sleeve being held" from appreeiabierotation Figure-2 is a section on line 2 2 of Fig. 1." -with respect to the casing byvirtue of such Figure 3 is a {detached elevation of the 7 frictional engagementtherewith. V inner sleeve of the bearing;

However,-it has been found 'difiicult to Figure :4 is a top. plan view of Fig. i provide bearings havingall the characterr'Figure 5 is a medial sectional View istics necessary t0= render them fully'eiih through one element of a positioning mem v 25 cient. The bearings'must not only be inherb 'r.

' ently sturdy toresist effectively tl e'tremen Fig r s jg b' tt i f Fi 5.

dous strains to which'they are exposed but Fi ji a dials u l View, h the yp o connectlongbetwew m and the ing a variational type of connection betweendrillste'm must be such asw ll permit. of the bearing and drill stem.

being understood that on a drill stemsev Figure 9 is an eleVationoft-he inner'b ar eral thousand'feet in length there will be afing. sleeve shown in Fig. '2.

' great number of anti-friction bearings, and Figure '10 is a medial sectional view'of a that the time element of mountingor dis b in lmvi g ng -h v -i ti Lt p 'Of -111011nti11g-the bearings is therefore an imconnection between it and the drillstem. 5.

portant factor in the ultimate cost of equip: Figure 11 is, a section ou line 11,-,11'0f ping a stem. Fig. .lQL k p 12 is an elevation of the inner bjear- Furthermore, theconnection must be such Figure as Willbassure that the bearings remainin ing sleeveshown in Fig. 10. V

40 acljustedposition on the stem in spite of Figure 18 is a medial sectionalyiew ofthe great displacement strains to whichthey a bearing having anothervariational type.

are exposed; It is also essential thatthe of connection betweenfit'and the 111 13 5136111; VJ bearings he comparatively simple in con- I Figure 14 isa fragmentary elevationoi struction, having a minimum number of Fig. 18 asview'ed from the right thereof. parts sothe danger of disorder is reduced to I Figure 15 is a fragmenta ry perspecti i aminimum.' V of the endoftheitool'jomt adapted to, taite; Therefore5 it may be considered as the the bearing sleeve shown in 13. general object of the present inventionto Figure 16-is fa medial section of a bearprovide an efiicient drill stem bearing which ing haying another variational type of conv 50 is relatively simple and sturdy of construc nection between itanol'the drill stem. a mo Figure 17 is a section on line 1717 of Fig. 16 V Figure 18 is an elevation of the inner bearing sleeve shown in Fig. 17; and V Figure 19 is a medial section 01 a bearing having another variational type of connection between it and the drill stem.

At is indicatedfthe casing of a deep well, there being within this casing a usual rotary drill stem 11 made up of pipe sec-- 'tions or portions 12 coupled byitool joints l8. s As is usual, each tool oint 1s. inadeup 7 o f a pin end or element 1% and a boxend at points intermediate the'tooljoints, 01 expressed otherwise and in contradistinc-v tion to the type of be 'ing' provided on the peripheral faces of the toolijoints themselves,

my bearings encircle the pipe 'whereit is exposed between tool oints. The bearings are positioned on the stem by association .drivingly connected to member;

vantage. Tered as means for keepmg the rotating drill with a memberrigidly connected to the pipe sections, hat part of the bearing which is to rotate with the pipe preferably being the pipe through said \Vhile I have shown several variational forms of bearings and connective elements, said forms have a common feature in that they include a pair of relatively rotatable inner and outer sleeves, the inner, sleeves being drivingly connected to the aforementioned rigidly 'mounted member. er sleeve, which is of greater diameter than the tool joint, is adapted to engage the casing peripherally so when it is pressed thereagainst it will be frictionally held against rotation, it following that drill stem rotation rotates the inner sleeve within the outer so the wear comes on the sleeves rather than on the casing and tool joints, to obvious ad- The bearingsmay thus be considstem out of direct contact, with the well casing. 7 V

Broadly, the bearing between sleeves may be of any suitable character,'su'ch as direct peripheral contact, but I'prefer to provide anti-friction members such as rollers or balls between the sleeves, though the showing and description 01 this provision are not to be considered as limitative on the invention, considered in its broader aspects.

As a feature of certain variational forms ofthebearingfihemner sleeve is not only drivingly connected to the rigidly mounted member on the stem, but it is also held by direct connection to said member against movement longitudally along'the pipe ineither directwn. In other variations, however,

The out? dependence is had u pon'the rigidly connected member only to connectthe sleeve drivingly to thecdrill stem and to hold the sleeve from movement longitudinally along the pipe in one direction, there then being provided another member on the pipe for limiting movement of the sleeve longitudinally in the opposite direction. The bearing assembly is preferablysuch that the positioning "of one sleeve on the pipe serves to position theother sleeve'the'reon, it following that when depende ce is had upon the rigidly connected member toposition the inner sleeve longitudinally on the stem, said member also serves to position the'entire bearing longitudinally on the stem. j v

While the exact location of the bearing on the stem is notcontrolling on the present invention, its most logical position is one closely adjacent the tool joint, for it is the joint which is naturally most prone to engage the casing. Accordingly, the tool joint may be utilized as the aforementioned rigidly connected member through which driving connection is made between the stem and inner sleeve, and through which the inner sleeve and'bearing may be longitudinally positioned on the stem, Or, in the event another rigidly connected member is utilize-dto provide the driving connection may beutilized to position or aid impositioningthe inner sleeve or bearinglongitudinally on the stem. Naturally, the utilization of the tool joint for any of these purposes dispenses with the necessity of adding an equivalent member to the stem and therefore is of advantage. I

In most well drilling operations, the stem is elevated and lowered through the medium of elevators which engage the downwardly facing annular shoulder defined about the V stem bythe lower end of the tool joint. Accordingly, it is desirable that this shoulder be left fully exposed for such elevator application, and it follows that ordinarily the bearing assembly preferably is on top a given tool joint, However, there are nowcoming into use elevators which include connection between the tool joint of other rigidly connected members and the inner sleeve and bearing which will allow the actual suspension of said sleeveand bearing from the tool joint or equivalent member.

.I'lowever, I have illustrated all the variatlons as being applied to the stem above the tool joint,rbut this is done merely as con-- venience and nyclaimsarelnot to be construed as being limited to the illustrated I arr-an ementand location of the bearings.v

In igs. 1 to 6, inclusive,- I- have shown an embodiment of the inventlon wherein a member otherthan the tool joint is rigidly connected to the drill stem and provides the driving. connection between said stem and the inner sleeve of the bearing. In this case, the tool joint is utilized to limit the movement of the bearing longitudinally in one direction along the stem, the rigidly connected member llmitlngvsuch-r longitudif nal movement in the other, direction; Of; course, the tool joint is also rigidly-con c n nected to the stem, but here it is: not employed as a driving connection between stem and inner sleeve.

I Bearing assembly .18 includes an fendthrust washer 19 whose, under-face is adapted toengage the upwardly facing; an-

nular shoulder presented about the upper.

pipe section 12 by thepin end 14: of joint 13, said shoulder 20 thus being adapted to limit movement of the bearing downwardly .7 ;along the stern, as'will hereinafter be apparent. l/Vasher19 has an upwardly extending annular flange 21 which is annularly spaced from the lower, external flange 22. on inner,

not necessarily, connection is made between thesleeve and washer as bypins orscrews 24 to hold them against relative rotation.

Sleeve 23 has at its upper end the'three external annular flanges 25, 26and 27, flange '26being intermediate the other two flanges.

and bein'gof greatest'diameten, Flanges22 and may be considered as vertically de-,- fining an annular recess 28 about thesleeve, V

the cylindric defining face 29, of this' r'ecess presenting the bearing surface of the sleeve, 7

though there are preferably providedF-rollers 30, or other suitable anti-friction mem-- bers, between this sleeve and the outer c0 axial and encircling sleeve 31, the bore defining wall 32' of the outer sleeve being the inner bearing face thereof. Sleeves 23 and 31 are thus-mounted for relative rotation and it willbe seen that they vmay be considered as inner and outer roller races, I

though 'itis to be understood that the provision of anti-friction members between the sleeves is not controlling onthe lnvention,

for the'bearing surfaces of the sleeves may be of a natureto allowdirect contact therebetween, as is readily understandable. V

The lower end. of sleeve 31 'is'provided with anannular fiange 33 which istaken in the annular space 34 defined by flanges 21 and 22. This flange coaction holds the outer sleeve from shifting-laterally. Flange 33 may extend inwardly somewhat beyond bearing face 32, the shoulder 35 thus provided acting with the upper shoulder 36 of flange to hold rollers 30 against displacementdownwardly. 'The upper end of sleeve 31 other end of cylindric sleeve 28, and preferably,'though T1 2 li dli has a counterbore r37within which is. set a washer 38,fth e"upper face o'fethis washer shoulderingagainst the downwardly facing shoulder 39 "of flange 26, thewasher overhanging 'bearingface 32. and,qwith. downwardly facing shoulder 40 of flange 25, serving to define the upperend of the annular space 4C1 ,an'nularly defined"by the two. sleeves, itjbeing within thi rollers; are mount-ed; the bearing,

Washer 138 is s recess that the, I

first slippedover the sleeve and-intocontact withfiangs 26, the rollersand outer sleeve;

seniblybeingsuch that thereafter the bearing 'may be handled as a unit witho-utdanger of falling apart during handling. The assembly, SlIPPGClOVGl upper pipe section 12c1ther i -om beneathiprior to conneotlon of said section and tool joint,-or fromabove if connection between V the pipe section and ]G'll1'i1- element has already been ,made,=;;assuining that-the tool oint element at the The'dianieterl o'f the outer sleeve 31' is appreciably greaterthan that of tool joint 13,

"pipe section has not as yet 1 andsomcwhat less than the bore of easing 10, as is apparent 1n.l. g. 2. Preferably, the

upper and lowerends of the outer sleeve are beyeled" or inclined inwardly as at 42, the lower end preferably meetinglflange 21 and the upper end preferably meeting flanlge26..

so there may engage the ends of the casing sections asthe bearing is passed througlithe couplingcoh lars I (not shown) of said leasing The beveled or conical ends 42 of the collarsmay thus be considered as means for guiding the bearings and joints as they pass through these caslng co-upllngs. I

adapted to be rigidly COIlIlQCbGCl'bO'bllQqClllll stem and through which the inner sleeve 23 is drivingly connected for rotationwithsaid stem-e Member a l 1S.lllSO 'adapteCllio1111111 movement of 'the'finnersleeve and bearing upwardly along theipipe, it forming with joint element 14 apair of opposed shoulders spaced longitudinally along 'the drill stem and between which the bearing is confined to limit its longitudinal movement;

means being provided to hold it'irigidly to pipe in anydesired position of adjust" ment; While I ,havejshown a preferred it ethod of thus fixing-it to the pipe, this means being generally; described radially expansible and contractlble pl'essural means, 1t will be understood that any suitable'type be no square-cut shoulders to' v .'=11'0 At 4A is indicated connector member As will 7 be apparent, member 44 is adapted to be adjusted longitudinally along the pipe,

of connection may be substituted without de'-' parting from'the spirit and scope of the in-' ventioni Member 44 is in theform of a collar 12W- ing a bore l5 adapted to take pipe section 12, and counterbores lfi and 417. Counterbore l? is adapted to take flange 27 of sleeve 23, and the lower edge of collar id is provided ith a plurality of angularly spaced, depending or longitudinallyprojecting locking lugs or fingers 48 which enter complementary notches 49 provided in sleeve flange 26-. These projections may also be consider ed as extending"longitudinally into tele: ;,s'eop1'c relation w th the lnnerslecve.

lefining wall 50 of counterbo-re 46 has ec )lementar to faces 51 it followin that ro'-' tation of collar as in one 1 direction with so 'rcspect to the pipe section acts to'constrict the ring sections tightly about the pipe-section, while rotation of the collar in theopposite direction allows said ri sections to loosen.-

The cam faces are preferably so fashioned that the tendency of the drill pipe during rotation thereof is to ti hten or radially contract the ring about the pipe. Thus, assuming that the drill stem be rotated normally .right-handedly, as viewed from above, any tendency to hold collar l4 from movement, which would be the equivalent of rotating said collar left-handedly as viewed from above, tends to'co'nstrict the ring about the 15 pipe and thus more rigidly hold the collar to the pipe;

7 After collar 44 has been actuated to convstrict the split ring and thus rigidly position said collar on the pipe set screw 56 may be 59 threadedthrough the collar and into contact with the ring section to hold the collar against undesired loosening movement.

Since projections or lugs 48 enter notches 49, it will be evident that the sleeve is drivinglyconnected' through said lugs and collar to the pipe section so as to rotate therewith, it following that when the outer sleeve ieri herall en a es the casin the drill] D b D7 stem and sleeve rotate within it,'the rota- 60 tional wear and'abrasive action thus being taken by sleeve elements rather than by the casing or tool joint. r

Now, the inner sleeve, length, maybe in peripheral contact'with eh'xthe pipe section, it following that there is tactwiththe pipe section.

throughout its no lost motion between the sleeve and pipe which-would t'endto "develop exte'ssive wear and consequentintermittent engagement between'the sleeve and stemtending to dama e either? orboth. This situation may be brought about by accurate machining of the sleeve to'iit pipe of given outside diameter. However, iir'actu'al practice standard pipe so varies in outside diameter'that it is practicallyimpos ib eto providesleeves of uni-- form inside d ameter which-will fit properly any two lengths or sections of pipe. Accord ingly, to rcnr [manufacture feasible, the

inner sleex' 'es are preferably, though not alle eifeets.-- This may either be done by so rigidly securin'g' the connected end of the lceve tothe drill stem as to prevent the free end 40f the sleeve 'from' being pressed or roc nto contact with the pipe section -(sucha provision may bctrue of the variation shown in? 19 of the drawings) or, such movement must be allowed the sleeve at its connected cndfas will permit said (Vonnected' end-to move coincidentallyv with the free end and thus allow the sleeve to move so, throughout its-length, it is in peripheral engagement with the pipe section at some one time extending lengthwise of the pipe section; In other words, the rotational driving connection between the rigidly connectedmember and one end of the sleeve must be such aswill allow limited and substantially uniform transverse movement of the'sleeve, and therefore of the bearing, throughout its length and with respect to the pipe, that is, so the sleeve is movable about thepipe with its axis remaining substantially parallel-with that of the pipe. It follows that the connection between sleeve and rigidly connected member is such that said sleeve has no inherent tend ency to be canted or pressed angularly in a manner to carryits free end only, into con- This result may be accomplished through the medium of a loose rotational" connection andthe allowance of. transverse play between the member rigidly connected to the stem and the inner sleeve; Such isthe medium employed here.

In'theemb'odiment illustrated in Fig. 1, thisyrotational loos'eness of the sleeve and member connection and the allowance for With a consequent I V transverse play is provided by making the lugs 48 sufficiently narrower than notches 49, g and allowing ample annular clearance between exterior peripheral :taces of the sleeve and the opposing nner peripheral:

faces foithe c deleting elements; For instance there isrannular clearance hetweenf flangeQTand the defining wall of cellar flange 47. There. is, alsoltransverseclear- V ante oetween lug e 8 audthe overhanging end of"? eye 3'l.' The upper ends; of the inner sleeve and bearing are thusallo'wed limited movement transversely .vit'h' respect' to the pipe coincidentally withrsuc'h move-;

ment of the lower end, it following that the sleeve "and hearing may move transversely and bodily to and fro with their coincident, axes remaining substant ally parallelto that In the drawings, while I have shown'one side of the outer sleeve in Contact w th the casing, for the sake offclear'nessI have: not

5 shown the bearing: and inner sleeve shifted contact with the casing.

transversely tomove saidsleeve into "Contact LWltli the vpipe sect1o'n, a would "normall occurhwhen the outer sleeve is in pressural l will now proceed to a description of thevariationaltypes of bearings and connective elements jbetweenthem andthe, drill "stem," it being "characteristic of all these variationsj that the inner sleeve of the bearing isldrivingly connected to the toolj oint itself for 1-otationwith the stem; However, it

will be distinctly understood that this illustration of; the utilization of the tool joint as the" drive connectivemember is {not to be construed as indicating that these variati'on'al 1 devices are-flimit'ed to such futilization' of the joint, forfthe' connection may as well be madetoa member other 'than the tool joint, just as in the embodiment" just described. "It will also bel rememberedithat whilethe bearings are shown, above the tool jbintithey' 'ma'y as well be 'provided below the joint, and, in certainof the variations,

actually suspended from the tool joint or an equivalent rigidly connected member. s

[Such of the elements or forma tlions of the variationaltypesof'bearings as are simi,- "litlitd those disclosed in thej first -d'escribed form will be 'givenfthe same reference, numf 'erals with letter 'ex'ponentsyan'd' it will be understood that their "features; and functions are generally thos cescribedln connect ll ,woum result,yopfpcqurse,wereftheprecess(whet-1E5:

'cjut'in the upper extent of thethr'eaded'pon i tionot standard tool joints; awa t-here 1 rote; be understood that wherever fIrfer c toaiflangegon the end of a tool jointel mentqf 1.30

with said first form and thereforefneediiiot" be discussed individually. Y SO3 alsoy it will 'be vunderstood that in all; the variations,

exceptthat shown in Fig. 19, clearances are provided between i the elements of the driv-. ling connection-- whereb there 1s. rOtatiQIIel looseness allowing the. heretofore described transverse, uniform movement of the sleeve throughout its length so its axis may remain substantially; parallel with that of i the stem, the purpose beingiidentical with that set ii -connection with the previouslydescribed embodiment. 1 k' I 'I11' Fig. ,7 tooljj'ointelement lta' is inter-x nally threadedlatj; lZato take 'pipe section 12a and preferably, though not necessarily, an annuiar tlange '60 extends upwardly from the endfoi the "element; At" angularly V spaced 'points about this flange are provided the und erfcut or dove-tail; recesses 61, these 1recessesopeningfto theupper end "and to bore of thejoint element. An inner sleeve 23a, generallysimilar to sleeve 23, is adapted 7 to encircle pipe section l2 cia'ndto bepntinto driving connection with the tool joint element, the connection also being such that the tool joint positionsthe innersleeve 1opgi,

tudinally on the stem.

' Sleeve 23a hasa lower fiangefQQa and an upper .annular; flange 26a, these flanges defining, the longitudinal extent of thefcy'lindric'z bearing face 29a, ,Depending from a ge-2 a r t ec'sp g gers-or longitudinally extending {lugs tSa, said lugseach having an, upper portionl62 jandfa" lower dove-tailed portion 63, said dove tail portions-being substantially complementary to' recesses 61. [At eachsideof a given-dove- .tail po'rtionand at, its upper end, there is provided a squarekcut shoulder 64:. p c Before'pipe section 1201 has been "thread ably; connected to element 14a, spring fingers or promotions 48a are pressed radially 1nwardly and introduced telescopically to the bore of flange'GO. When the projections are 'in register with recesses 49a they sprlng thereintfo and pip section; 12a may: therec afterbe passed throughthesleevebOle and into threaded connection with the joint element." Fingers- "Sd thus engage the tool joint element in, a manner to connect sleeve 23a'and element lea; drivingly so the sleeve will rotate with the stem; and thefldove-tail I formation of the fingers and recesses serves to hold the jointelement and sleeve against relative longitudinal movement.--

Itfwill be understoodthat recessestl- -inay be out directly in the upper ends or stand) ard-tool joints,-though it-isjpreferred to pro-'- vide the extension flange iori annular apron v 60 inhorder' that the provision of the; recesses mayfn otzlessen the extent of threaded engagement between tool joint la nd pipe see- I tio'n "below standard, a lessening which his i'sjf i as . not, tobe construed as limiting the invention to a'tool joint having such a flange.

'Oute1ffsleeve31a is, generally similar to Sleeve 31, being longitudinally positioned on 5 the drill stem by 'inneri sleeve flange 26a at "one, end," and at thev other end by the upwardly' facing annular shoulder a present 7: ed by flange where it extends radially outfwardly beyond inner s'leeveflange 22a. It may be noted that preferably the squ are cut '7 shoulder 64 of fingers 48a also engagethe fiend face of flange 60. i

, Sleeve 31a is rotatably mounted on the inner sleeve, and is preferably, though not necessarily, annularlyspaced therefrom by anti-friction means such as hardened rollers 30a. f H I T ,l-Though this is not essential to the inven- ,ti'on', since the dove-tail connection, between vents longitudinal separative movement thereof, 1' may provide a collar above the flange 26a of the inner sleeve and releasably fixed to pipe section 12a by set screw 66. In the event of unduefwearin the dove-tail connection or if the connectionbe designed to provide only for ai'otational driving-connection' between the inner sleeveand the 'tool joint element, collar 65 is adapted to hold the inner sleevefand hence the bearing assembly I from movement longitudinally a1o1'1'g"'1;11e stem in a given direction. It also serves the purpose of taking frointhe hearing assembly such strains as might otherwise :beimposed thereon by the tendency of; the

pipe sectionto bend, i

In Figs. 10,111 and 12"I' have shownv a variation generally similar to Fig. 7, but differing in the type of dove-tail connection between the inner sleeve of the bearing and the tool joint element. 1111 this case theflange 60?) at the upper end of joint element l lb is provided vrith an annular under-cut groove 68, the entrance mouth to this groove,

v upwardly and inwardly inclining face's 695 which are substantially complementary to ,5 the angular :walls {'of the under-cut v groove v68. Before pipe section 126 has been threadably vconnected to joint element 14:?) fingers 48?) are sprungiinwardly, the chamfer .69

aiding in springing} the fingers in ardly as theisleeve is pressed downwardly, and as soon asheads63b, register w thithe under cut recess-in flange 6Qb,,.;they r sp'ringthereintol Thereafter pipe sectionl2b maybe ,threaded into connection withjointclement' lab} :The overd angingwallof thennderpale nee ismaria he gf e 9 woe the tool joint element and inner sleeve pre- .tion the inner sleeve longitudinally on the drill stem, and in order toconnect the oint element 'andinner sleeve drivingly so said sleeve rotates'with the drill stem, pins are extended from flange 60b radially into re; c'css 68 at opposite sides of projections 48b."

The remaining elements of the hearing are substantially the same and have the same functions asthose described in connection with'Fig. 7. They are indicated by similar reference numerals with the exponent b.

It may be stated that in the forms shown v in F igsl 7 and'lO such clearances exist in play therebetween, and this looseness may be considered as allowing relative gyratory movement between the bearing and tool joint or equivalent rigidly fixed member on In the" variations illustrated in 13 to 15, inclusive, inner sleeve 230 is provided with a lower external flange 220 from which depend a pair 7 of diametrically opposite dove-tail lugs 480. Sleeve 23c is threaded at its upperend 71, and below the threaded portion is provided an external annular ,fiang'e 72. About the sleeveand longitudinallypositioned by flanges 22c and'72 may be the hardened rollers 300. .An outer sleeve 310 is rotatably mounted'on the; inner sleeve through the medium of rollers 800,

over the inner sleeve atone end by' its engagement withfla'nge 22o and atv its other end by retention collar 73 which is threaded on theinner sleeve at71 and preferably into engagement with flange 72. A set screw T l may be utilized to-hold the, retention collar releasably in adjusted position. The flange 600 on-the upper end of joint element 14 is provided with a pair of dia- Vmetric ally opposite under-cutor dove-tail ways. or recesses l9cfsaid ways beingn substantially complementary to lugs 480-. Before. pipe section 120 has been threadedinto joint element 140, the fully assembled bearing may be'passed transversely across the end of the tool joint el e1nent,'lugs 4 being held in alinement with recesses 490 so they enter such re'cesses dnring such transverse movement ot thebearing. After the sleeve 3y and'tool joint elementzlare substantiallyin axial alineinent, at which time lugsASo are fullyentered in recesses,49c, pipe section 120 is, lowered down through the sleeve bore and into threadedconnection with the tool the driving connections between the sleeves and tool joint elements as to provide rota-i, tional looseness and allowance of transverse the drill stem, such gyratory movementpt that 151 and is held aga nst longitudinallmovement' said bearing including an inner and an outer sleeve capable of relative rotation, said inner sleeve being drivingly connected to the member so as to rotate with the stem, the connection between the innei sleeve and member being loose and thereby allowing relative gyratory movement between them. V

2. In combination with a rotary drill stem comprising section'sof drill pipe and tool.

joints coupling the sections,-and a bearing 40 sprung radially into a registering recess pro:

about one of the pipe sections, said'bearing including an innerand an outer sleeve capable ofrelative rotation, said inner sleeve being drivingly connected to one of the tool joints associated with said section so as to rotate withthe stem, the connection between the inner sleeve and joint beingeloose and thereby allowing relative gyratory movement between them.

3. In combination with a rotary drill stem, a member rigidly connected to said stein, a

bearing about the pipe portion of the stem,

said bearing including an inner and an outer sleeve capable of relative rotation, and a driving connection between the inner sleeve and member, vsaid connection including a resilient projection on the inner sleeve extending longitudinally into the member and vided in the member at a point intermediate itsends."

4. Inrcombination with a rotary drillstem, a member rigidly connected to said stem, a hearing about the pipe portion of the stem, said bearing including aninner and an outer sleeve capable *of relative rotation, and a driving connection between the inner sleeve and member, said connection including a resilient, headed projection on the inner sleeve extending longitudinally into the member,

said projection being sprung-radially into a registering undercut recess provided in-said member. 1 1

5. In combinationwith a rotarydrill stem, a member rigidly connected to said stem, a

and a projectioni on an end of, said inner sleeve and projecting longitudinally between said pipe portion and flange, said PIOjBCtlOli having a head portion sprung into said undercutrecess. A

' 6. In combination with a rotarydrill stem,

a bearing about thestem andincluding an inner and an outer sleeve capable of relative rotation, and a rotative-driving connection between the stem and inner sleeve, said connection being aloose one whereby there'is allowed gyration of the inner sleeve with respect to the stem.

In witness that I claim the foregoing I have hereunto subscribed my name this 26 day of July, 1926. 7

- JOHN GRANT.

bearing aboutthe pipe portion of the stem, I

said vbearing including an innerand an outer sleeve capable of relative rotation, and a; driving connection between-the inner sleeve and member, said connection includingv an 7 annular flange about an end of the. member and spaced annularly-from saidipipe portion, sa drflangehaving an undercut recessginit, 

